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 * Licensed to the Apache Software Foundation (ASF) under one   *
 * or more contributor license agreements.  See the NOTICE file *
 * distributed with this work for additional information        *
 * regarding copyright ownership.  The ASF licenses this file   *
 * to you under the Apache License, Version 2.0 (the            *
 * "License"); you may not use this file except in compliance   *
 * with the License.  You may obtain a copy of the License at   *
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 *   http://www.apache.org/licenses/LICENSE-2.0                 *
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 * Unless required by applicable law or agreed to in writing,   *
 * software distributed under the License is distributed on an  *
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY       *
 * KIND, either express or implied.  See the License for the    *
 * specific language governing permissions and limitations      *
 * under the License.                                           *
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package org.apache.james.transport.matchers;

import java.io.IOException;
import java.util.regex.PatternSyntaxException;

import javax.mail.MessagingException;

/**
 * Initializes RegexMatcher with regular expressions from a file.
 *
 */
public class FileRegexMatcher extends GenericRegexMatcher {
    
    /**
     * @see org.apache.james.transport.matchers.GenericRegexMatcher#init()
     */
    public void init() throws MessagingException {
        java.io.RandomAccessFile patternSource = null;
        try {
            patternSource = new java.io.RandomAccessFile(getCondition(), "r");
            int lines = 0;
            while(patternSource.readLine() != null) lines++;
            patterns = new Object[lines][2];
            patternSource.seek(0);
            for (int i = 0; i < lines; i++) {
                String line = patternSource.readLine();
                patterns[i][0] = line.substring(0, line.indexOf(':'));
                patterns[i][1] = line.substring(line.indexOf(':')+1);
            }          
            compile(patterns);
                  
        }
        catch (java.io.FileNotFoundException fnfe) {
            throw new MessagingException("Could not locate patterns.", fnfe);
        }
        catch (java.io.IOException ioe) {
            throw new MessagingException("Could not read patterns.", ioe);
        }
        catch(PatternSyntaxException mp) {
            throw new MessagingException("Could not initialize regex patterns", mp);
        } finally {
            if (patternSource != null) {
                // close the file
                try {
                    patternSource.close();
                } catch (IOException e) {
                    // just ignore on close
                }
            }
        }
    }
}
